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#! /usr/bin/env python
# -*- coding: utf-8 -*-
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
#
#
# Adapted from example dags in airflow-provider-ray, see also
#
#  https://github.com/anyscale/airflow-provider-ray/blob/main/ray_provider/example_dags/ray_pandas_example_dag.py
#

import json

from airflow.decorators import dag
from airflow.decorators import task
from airflow.utils.dates import days_ago

default_args = {
    'owner': 'airflow',
}


@dag(
    default_args=default_args,
    schedule_interval=None,
    start_date=days_ago(2),
    tags=['example'],
)
def taskflow_etl():
    @task()
    def extract():
        data_string = '{"1001": 301.27, "1002": 433.21, "1003": 502.22}'

        order_data_dict = json.loads(data_string)
        return order_data_dict

    @task(multiple_outputs=True)
    def transform(order_data_dict: dict):
        total_order_value = 0

        for value in order_data_dict.values():
            total_order_value += value

        return {"total_order_value": total_order_value}

    @task()
    def load(total_order_value: float):
        print(f"Total order value is: {total_order_value:.2f}")

    order_data = extract()
    order_summary = transform(order_data)
    load(order_summary["total_order_value"])


taskflow_etl_dag = taskflow_etl()